Read the recommendation

This works on iPhone, Android and the web. The engine and its answer are the same on all three. The layout differs a little, as noted below.

Where it appears

A reading runs when a shot is tasted: when you save a shot with its tasting, or a tasting later. On iPhone the sheet turns into The reading. Android shows the same card and the details under it. On the web it appears under the log panel as Recommended next action. While you pick tags, a preview of the reading follows along. Nothing is saved until you save the tasting.

The card: one change

The card’s title is the change to make next: Grind finer, Grind coarser, Yield: more, Yield: less, Fix puck prep / distribution, or Settle & lock: balanced when there is nothing to fix. Under it, one or two sentences say what to do, with the number where there is one: the grind setting to go to on your own collar, or the yield to stop at. Most grind changes also remind you to purge a few grams, so the old grounds do not end up in the test shot.

On the web, a grind change shows the move from your setting to the new one, and Apply to collar sets the grinder to it.

The confidence

The badge beside the title reads high confidence, medium confidence or low confidence. It is the engine’s grade for how directly the evidence points at that cause, set by the rule that matched, and not a percentage. A clean pattern (sour cup, even flow) gets high. A cause that needs a second shot to confirm gets low, and its advice often says so (“only if it repeats”).

The ranked causes

The engine works through the shot in a fixed order. A puck that choked or channeled explains the cup by itself, so it is checked before anything is blamed on the coffee. The first cause it lands on is the card. The others it weighed come after it, each with its own change and confidence: under Also considered on iPhone, after the card on Android, and in Ranked diagnostics on the web (which lists the first one again).

Above them, What it read (iPhone) lists the facts the engine started from: the coffee’s age when the shot was pulled, its dial category, and the shot’s dose, yield, ratio, time and flow. The small codes on the card are the rules from the knowledge base it relied on.

Warnings come with the reading too. One appears when you have pulled four or more shots of this coffee today, because a tired palate can mislead you.

Why never two changes

The reading ends with Change one thing at a time. If you grind finer and pull longer in the same shot, the next shot cannot tell you which one helped. Make the change on the card, pull, taste, and read again. The other causes show the engine’s thinking. Do not stack them on top.

The card names one change, and so does each cause after it. A second change that might help comes later in the list, for when the first did not: brewing cooler when a shorter shot is still bitter, or a paper filter in the bottom of the basket when the cup still tastes dry after more yield.

Why a shot gets no reading

• It has not been tasted. It waits under Awaiting tasting on the Cockpit. See log a shot and taste it.
• The grind setting is not confirmed. The engine will not dial against a setting it cannot trust. On iPhone the reading says The engine did not read this shot and offers Set collar position, then Read it again. Android offers Set grind. The web offers It’s at … with your current setting. Confirm where the collar really is, as measured, and the reading runs.
• The machine is not set up for espresso. Its shots are kept as a record and not read. The card says No reading for this prep style, names the machine’s prep style, and points to Equipment: if the machine makes espresso, edit it there and set its prep style to espresso. The phones mark such a machine Records only.
• There was no connection yet. The shot and the tasting are saved on the phone, and it says Tasting saved. The reading runs when it syncs (or Shot logged with tasting. The reading runs when it syncs). Once the phone is back online and the tasting has reached the server, the phone says The reading is ready. Open the shot in History. Open the shot from History and read it under The reading. If the engine did not read it, fix what it says, then tap Read it again there.
• The collar was re-described after the shot was pulled, and the shot’s setting no longer exists on it. Read a shot pulled after the change.

When a shot reads balanced, the next step is yours: if it tasted right, lock it as the recipe. See locked recipes.